1. Field of the Invention
The invention is in the field of remotely driven free displacer cyrogenic coolers based upon the balancing force at a frictional seal between an ambient temperature volume and a working fluid volume.
2. Description of the Prior Art
Generally, the ambient temperature volume of a cyrogenic cooler is comprised of one pneumatic volume which influences the movement of the free displacer according to the compressed state of the gas in the pneumatic volume, which acts against the sinusoidal pressure waves in the working fluid. The free displacer therefore follows a sinusoidal oscillatory wave pattern in which the pneumatic volume essentially does not alter the displacer waveform but only acts to restore the displacer back to its position with some slight phase shift while still supporting the sinusoidal movement thereof. The present dual pneumatic volume means alters the displacer movement by causing dwell times at both the top dead center (TDC) and bottom dead center (BDC) of the displacer movement waveform.